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## Homework Statement

King Arthur's knights fire a cannon from the top of the castle wall. The cannonball is fired at a speed of 46 m/s and at an angle of 25°. A cannonball that was accidentally dropped hits the moat below in 1.2 s.

(a) How far from the castle wall does the cannonball hit the ground?

m

(b) What is the ball's maximum height above the ground

## Homework Equations

Vf= V0 +at

Deltax= V0t+ .5at^2

Vf^2= V0^2 +2ax

SOHCAHTOA

## The Attempt at a Solution

I don't understand why I'm getting this wrong. I begin by separating it into two motions, horizontal and verticle. Using trigonometry I found that for the horizontal motion, the velocity was a constant 41.7 m/s. The Horizontal acceleration is 0, and the time is 1.2. I found these by using the listed equations above. 1.2 seconds is the time for both the verticle and the horizontal motions, by definition.

For the veritcle motion, the acceleration is a known -9.8, the time is constant between the two, the initial velocity is 19.4 (using the equations), the final velocity is -7.64 (using the equations), and the deltax is 16.2. Yet my answers are not working. Did I do something wrong mathematically. I've drawn the motion of the object, and I still don't understand.

I don't have the change horizontally becasue my number wasn't working right. For the second question, I made the final velocity zero horizontally (so that it was at the change of direction, the highest point) and then added that to my original 16.2. This was wrong as well. What am I doing incorrectly?